The statements in this section merely provide background information related to the present disclosure. Accordingly, such statements are not intended to constitute an admission of prior art.
Vehicle systems include powertrain systems that provide tractive torque for propulsion. Powertrain systems may include hybrid systems, all-electric systems, and extended-range electric systems that may be configured to operate in various operating modes to generate and transfer torque to a driveline. Such powertrain systems use torque-generative devices, clutches and transmissions. Torque-generative devices include internal combustion engines and electrically-powered motor/generators, i.e., electric machines. Known electric machines interact with energy storage devices, e.g., high-voltage batteries. Known high-voltage batteries include those fabricated from a plurality of lithium-ion cells. Known energy storage device devices configured to store electric energy on-vehicle include a plurality of high-voltage electrical cells and ultracapacitors, among others.
Known parameters associated with monitoring an energy storage device include a state-of-charge, current, and voltage. Available battery power describes battery power limits that include an allowable range between minimum and maximum allowable battery power levels. Allowable battery power limits are preferably established at threshold levels to prevent either overcharging or overdischarging of an energy storage device. Exceeding allowable battery power limits may result in damage that reduces service life of an energy storage device. It is known that overaggressive limitations in the allowable battery power limits may result in underutilization, with attendant reduction in tractive torque generated using electric power. In hybrid powertrain systems and extended-range electric systems, there may be a corresponding increase in tractive torque generated using an internal combustion engine.